In this issue of ARCHIVES, Guis et al1 describe a family with autosomal dominant susceptibility to malignant hyperthermia (MH) and muscle histologic characteristics showing multiminicores in the absence of symptoms of weakness or myopathy. There was high concordance in this family among in vitro sensitivity to caffeine and halothane, multiminicores, and novel mutations in the skeletal muscle ryanodine receptor (RYR1) gene. This family illustrates the overlap of these diseases (Table 1) and again demonstrates the power of genetic analysis to either clarify or confuse the boundaries between clinical phenotypes. It also illustrates the potential complexity of this group of diseases in which the "genetic environment" of polymorphisms is critical to the phenotype.
Mathews KD, Moore SA. Multiminicore Myopathy, Central Core Disease, Malignant Hyperthermia Susceptibility, and RYR1 MutationsOne Disease With Many Faces?. Arch Neurol. 2004;61(1):27-29. doi:10.1001/archneur.61.1.27